3D printer for integral manufacturing of functionally graded material and forming structure, and working method thereof

Abstract

The invention provides a 3D printer for integral manufacturing of a functionally graded material and a forming structure, and a working method thereof. A feeding module, a mixing module and a printingsprayer are split; and through ingenious arrangement of the components, integral manufacturing of the continuous functionally graded material and the complex three-dimension structure can be achieved. The 3D printer has the characteristics and outstanding advantages of active, efficient and uniform mixing of various materials, high print resolution (due to micro-nano microscale characteristic structure printing), diverse applicable materials, high production efficiency, low cost and simple structure; and particularly, the 3D printer can achieve integral manufacturing of the continuous functionally graded material and the complex three-dimension structure based on material composition and microstructures.

Description

technical field [0001] The disclosure belongs to the technical field of additive manufacturing and functionally graded material / structure manufacturing, and relates to a 3D printer and a working method for integrated manufacturing of functionally graded materials and forming structures. Background technique [0002] The statements in this section merely provide background information related to the present disclosure and do not necessarily constitute prior art. [0003] Functionally Gradient Material (Functionally Gradient Material, referred to as FGM) refers to the use of advanced composite technology during the preparation of materials to make the micro elements of the material (including material components and microstructure) continuous (or quasi-continuous) in a specific direction. ) gradient change, so that the macroscopic properties of the material also present a continuous (or quasi-continuous) gradient change in the same direction as a heterogeneous composite materi...

AI Technical Summary

Problems solved by technology

[0006] According to the existing research results and information that have been published at home and abroad, the 3D printing technologies and processes that have been proposed for the manufacture of functionally graded materials / structural parts mainly include: directed energy deposition (LENS), laser cladding, and fused deposition modeling (FDM). , polymer injection (Polyjet), powder bed fusion, etc., but, according to the research of the inventor, it is found that these existing 3D printing technologies still have many defects and deficiencies when manufacturing functionally graded materials / structural parts: (1) Inhomogeneous mixing of ingredients

These existing technologies do not provide a dedicated mixing unit (especially active mixing of materials), resulting in uneven mixing, which leads to the inability to prepare real high-performance functionally graded materials / structural parts

For example, the existing LENS, laser cladding, FDM and other technologies mostly adopt the integrated nozzle / print head structure, and it is completely impossible to achieve uniform mixing of multiple materials in the integrated nozzle, especially LENS and laser cladding materials are the components of materials. After spray deposition, the mixing is carried out in the molten pool, and the mixing effect is even worse

The multi-nozzle structure used in the polymer jetting process is also the mixing of multiple materials before they are solidified after deposition, which cannot achieve complete and uniform mixing of multi-component materials

The powder bed fusion process restricts its ability to achieve uniform mixing of materials (especially for the feeding method of powder coating), and there is a serious problem of material waste; (2) various existing 3D printing technologies cannot realize continuous functional gradient materials / The manufacture of structural parts can only realize the manufacture of quasi-continuous functionally graded materials / components, and cannot produce functionally graded materials / components in the true sense; (3) The processing accuracy is low, and all existing processes cannot achieve micro-scale functional gradients In the manufacture of structures, the minimum feature resolution is difficult to achieve below 100 microns, especially no technology can realize the manufacture of high-resolution feature structures below 20 microns; (4) These existing technologies are difficult to achieve due to the limitation of forming accuracy The manufacture of functionally graded materials or structural parts based on microstructure changes is mostly realized by adjusting the composition ratio of materials to realize the manufacture of functionally graded materials or functionally graded structures; (5) it is impossible to realize the integrated manufacture of functionally graded materials and three-dimensional structures, Most of them are integrated manufacturing of simple two-dimensional or 2.5-dimensional structures; (6) it is difficult to realize the manufacture of complex three-dimensional functionally graded structural parts; (7) the production efficiency is low and the stability of the manufacturing process is poor, such as LENS, laser cladding, FDM, etc., due to During the printing process, the material ratio is constantly changing, and the printing process parameters (laser power, nozzle heating temperature, etc.) must also be adjusted accordingly, resulting in poor process stability and low printing efficiency in the entire printing process; The mixing and printing functions are integrated, and a strict sequence and synchronization relationship must be ensured for feeding, mixing and printing, otherwise it will be difficult to successfully print out the required functionally gradient materials and molding structures, and the improvement of processing efficiency will be greatly limited;( 8) The types and shapes of available printing materials are limited, and the printing materials need to be processed into the required shape and size in advance

For example, the current materials suitable for LENS and laser cladding processes are basically powder and wire, and there are strict restrictions on the shape and geometric dimensions of powder and wire; FDM is currently suitable for wire, and its geometry The size is also strictly limited; polymer injection is currently only suitable for very low-viscosity photosensitive resin materials; powder bed fusion is suitable for powder materials, and its geometry and size have stricter restrictions; (9) Each manufacturing technology is suitable for There are also strict restrictions on suitable forming materials. LENS, laser cladding and powder bed fusion technologies are mainly used for metal-based functionally graded materials and structure manufacturing. FDM is mainly used for thermoplastic-based functionally graded materials / structures. Polyjet is mainly used for Manufacturing of photocurable resin-based functionally graded materials / structures; (10) equipment and processes are complex and production costs are high

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